Pierre, S.D. ? A powerful spring storm swept through the northwestern Plains on Wednesday, dumping up to 2 feet of snow that closed major highways, cut power to hundreds and was blamed for at least four deaths.

More than 2,000 homes and businesses lost power in South Dakota’s Black Hills, and many schools were closed. Some customers in North Dakota could be without electricity until Friday.

The heaviest snow was reported in the Black Hills, with 24 inches at Lead and Rochford, the weather service said. Sundance, Wyo., reported 13 inches of snow by midmorning with wind gusting to 60 mph.